We propose to investigate methods for the synthesis of beta-L- rhamnose-1-phosphate (I, beta-L-rhamnopyranosyl phosphate) and beta-L- fucose-1-phosphate (II, beta-L-fucopyranosyl phosphate) by reaction of the sugar 2,3,4-triacetates with o-phenylene phosphorochloridate, III, in order to make available the intermediates required for the synthesis of all of the possible beta-L-rhamnosyl and beta-L-fucosyl nucleotides, in particular, beta-L-rhamnopyranosyl (thymidine 5'-pyrophosphate) (dTDP-beta-L-rhamnose, IV) and beta-L-fucopyranosyl (guanosine 5'- pyrophosphate) (GDP-beta-L-fucose, V). These beta-glycosyl nucleotides are widely occurring cellular constituents involved in the glycosylation of the endotoxins of Salmonella, blood group substances, and other glycoproteins and polysaccharides.